It's not a 0 sum game so much as an equilibrium expression. They're just putting their thumb on one side of the scale. Where the extra evaporation comes from a

It's not a 0 sum game so much as an equilibrium expression. They're just putting their thumb on one side of the scale. Where the extra evaporation comes from and how it affects global climates is too tricky to predict but that's not going to stop them so we'll just have to live through it.